Weft carrier control apparatus

ABSTRACT

An improved control apparatus for controlling actuation of the gripper finger of a weft extending carrier in a shuttleless loom of the gripper type. The apparatus being adapted to control actuation of the gripper finger to release the weft which was held thereby while being drawn through the shed and to prevent its actuation during the carrier&#39;&#39;s movement toward the shed to receive the next pick of weft.

US. Patent Dec. 23, 1975 Sheet 1 of2 3,927,699

US. Patent Dec. 23, 1975 Sheet 2 of 2 3,927,699

WEF'I CARRIER CONTROL APPARATUS BACKGROUND OF THE INVENTION 1. Field ofthe Invention The invention relates to shuttleless looms of the gripperor single pick insertion type in which weft yarn drawn from a stationarysource is inserted as individual picks into separate sheds of warpthreads. In particular the invention pertains to a control deviceeffective upon the weft extending carrier for controlling actualion ofthe carrier's gripper finger which is adapted to grip the weft as it isextended through the shed to complete a single pick.

2. Description of the Prior Art In shuttleless looms to which theinstant invention is applicable each pick of weft is inserted by tworeciprocating carrier members disposed in opposed relation and which arefixed on the free ends of flexible tapes that are caused to be wrappedabout and extended from oscillating wheel members at each side of theloom. One of these carriers is commonly referred to as the insertingcarrier and the other as the weft receiving or extending carrier.

In shuttleless looms of the single pick insertion type the weft yarnremains threaded through an eyelet in the rear wall of the insertingcarrier and extends in one direction to its source of supply and in theother direction to the selvage or fabric edge.

To form single picks the weft yarn must be clamped, held, then cutadjacent the shed after the inserting carrier is withdrawn from thelatter. In preparation for the following pick, the weft yarn ispositioned in such a manner as to be caught by a clamping element in theforward wall of the inserting carrier prior to the latters entrance intothe shed. The clamped yarn is then released and that portion extendingbetween the front and rear walls of the inserting carrier is properlypositioned for positive transfer to the extending carrier. The extendingcarrier grips the weft adjacent its cut end by means of a grippingfinger pivotably mounted intermediate its ends within said carrier. Thisgripping finger extends within the carrier for a substantial portion ofthe longitudinal length of the latter and includes a biasing means forcontinually urging the leading end thereof into a groove of conformingconfiguration formed in the hooked leading end of the carrier. Thisbiasing means is in the form of a coil spring one end of which seatsagainst an inner rear vertical wall of the carrier and the opposite endis caused to bear against the finger immediately adjacent to itstrailing end. This trailing end is in the form of an integral andlaterally extending lip which is continually urged forwardly by the coilspring causing a portion thereof to protrude beyond the'forward side ofthe carrier.

As the carrier is being withdrawn from the shed while extending a pickof wefi thereacross, the protruding lip on the carrier is caused tocontact a fixed member that depresses the lip inwardly causing at thesame time the release of the gripped end of weft by pivoting the leadingend of the finger out of the groove in the carriers hooked leading end.

This means of releasing the extending carriers grip on the weft hasperformed satisfactorily; however, the fixed member which is effectivein pivoting the finger during withdrawal of the carrier from the shed isalso effective in pivoting the finger as the carrier is caused to movetoward the shed to repeat the cycle of receiving and extending the nextpick of weft. This means of actuating the gripper finger on both thewithdrawn and insertion movement of the extending carrier causes what isconsidered premature life expectancy of said carrier. Repeatedcompression and relaxing of the coil spring for effecting pivotalmovement of the carriers gripper finger necessitates frequentreplacement of these springs due to fatigue failure which of course isaccomplished by excessive loom down time and production loss whilemaking the necessary repairs and replacement.

The weft carrier control apparatus according to the present inventionprovides a means which alleviates the above condition substantially bycausing the carriers gripper finger to be actuated only once during eachpicking cycle rather than twice as is prevalent with known devices ofthe prior art.

SUMMARY OF THE INVENTION The improved control apparatus for controllingactuation of the gripper finger of a weft extending carrier includes acam member mounted adjacent to the edge of the fabric and disposed so asto engage the forwardly extending lip of the carriers gripper fingerduring withdrawal of the carrier from the shed. The gripper finger atthis time is pivoted and releases the weft yarn it was drawing throughthe shed.

The cam member is spring biased in a downwardly direction as well as ina lateral direction which continually urges its camrning surface to thatposition to be engaged by the lip of the gripper finger. The leading endportion of the forwardly extending lip of the gripper finger is wedgeshaped and defines a plow type camming surface which as the carrier iscaused to move toward the shed it engages the outer end of the cammember and lifts the latter so that the upper surface of the lip movesalong the lower surface of said cam member as the carrier moves towardand into the shed. Actuation of the gripper finger during movement ofthe carrier toward the shed is thus prevented and substantiallyincreases operating life of the gripper finger's biasing means.

It is a general object of the invention to increase the operating lifeof weft extending carriers for gripper type shuttleless looms.

A further object is to extend the life expectancy of gripper type wefiextending carriers by providing means to substantially reduce, relativeto carriers of the prior art, the frequency of actuation of the carriersgripping finger during each picking cycle.

These and other objects of the invention will become more fully apparentby reference to the appended claims and as the following detaileddescription proceeds in reference to the figures of drawing wherein:

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of aportion of a gripper type shuttleless loom showing the weft carriercontrol apparatus according to the invention applied thereto;

FIG. 2 is a plan view of the weft carrier in FIG. 1 showing the cammember for actuating the gripper finger to release the weft heldthereby;

FIG. 3 is a view in end elevation of the apparatus in FIG. 1 as seenlooking from the left-hand side thereof;

FIG. 4 is a view similar to FIG. 3 but showing the carrier withdrawnfrom the shed a distance sufficient for the cam member to actuate saidcarriers gripper finger;

finger and that position to which it is elevated to prevent actuation ofsaid finger; and

FIG. 7 is a plan view of carrier in FIG. 6 showing the biasing means forlaterally urging the cam member toward the carrier.

DESCRIPTION OF THE PREFERRED EMBODIMENT As the general construction andoperation of a loom to which the present invention is applicable is wellknown and familiar to those conversant in the art, and as the inventionis entirely concerned with an improved weft carn'er control apparatusfor such looms, it is only considered necessary here to illustrate anddescribe those parts which are directly concerned with a preferred formof the invention.

In the figures of drawing the weft extending carrier is indicatedgenerally by numeral 10 and is fixed to the end of a flexible tape 11which in a known manner is caused to be wrapped about and extended froma tape wheel disposed at the side of the loom not shown.

The usual form of reed 12 is carried on a reciprocating lay beam 13(FIG. 3) that is provided with a raceway 14 for guiding the flexibletape 11 and its carrier 10 during the performance of their intendedfunction all of which is well known to those conversant in the weavingart.

The carrier 10 is of the conventional elongated configuration havingupper and lower surfaces 15 and 16 respectively that are disposed inspaced and aligned relation and which join at the leading end of thecarrier to form a weft engaging hook 17. At the opposite or trailing endof the carrier the upper surface 15 tapers downwardly as shown at 18 inFIG. 6 where it joins with the lower surface 16 and forms a means fordeflecting the warp yarns during withdrawal of the carrier from theshed. As shown in FIGS. 2 and 7 a web or rear wall 19 extends forwardlyfrom the carriers trailing end for a portion of the length of thelatter. In the space intermediate the upper and lower surfaces 15 and 16the carrier is provided with a gripper finger generally indicated bynumeral 20 pivotably assembled intermediate at ends therein by means ofa pin 21. This gripper finger 20 extends for substantially the fulllength of the space provided between the surfaces 15 and 16 and isprovided at its trailing end with an off-set lip generally identified bynumeral 22 and disposed so as to protrude from the forward side of thecarrier 10.

A biasing means in the form of a coil spring 23 (FIGS. 2 and 7) islocated within the space provided between surfaces 15 and 16 and isdisposed so that one end thereof seats against the rear wall 19 and theother end against the inner or rearward side of the off-set lip 22. Thiscoil spring 23 is assembled under tension and serves to continually urgethe off-set lip forwardly which in turn urges the leading end 24 of thegripper finger (FIGS. 2 and 7) rearwardly and into a groove 25 ofconforming configuration formed in the hook 17 where it is effective ingripping a pick of wefi 26 while drawing the same through the shed.

The forward vertical side of the off-set lip 22 has a portion of saidside which is directed at an angle oblique to the remainder thereof andprovides a first cam engaging surface 27 which serves to effectactuation of the gripper finger 20 and release of the weft as thecarrier is being withdrawn from the shed. This offset lip 22 alsoincludes at its leading end an extension of its upper horizontal surfacewhich tapers angularly downward to meet the lower surface thereof anddefines a second camming surface or a plow type cam 28. Cam 28 iseffective on the weft carrier control apparatus, now to be described toprevent actuation of the gripper finger when the carrier is caused tomove toward the shed.

The weft carrier control apparatus is identified generally in FIGS. 1,3, 4 and 5 by numeral 29 and as shown in FIG. 3 includes a supportbracket 30 which attaches to the lay beam 13 by means of cap screws 31.A locating bracket 32 is assembled to the support bracket 30 by means ofbolts 33 and includes horizontally disposed slots 34 and 35 throughwhich said bolts 33 extend to provide means for controlling the distancebetween the shed and the control apparatus 29. The support bracket 30also includes slots 36 and 37 that are vertically disposed through whichbolts 33 extend and provides a means for vertical adjustment of thecontrol apparatus 29 (FIG. 1).

A cam retaining member generally indicated by numeral 38 having a lowerplanar surface 39 assembles on the top of the locating bracket 32 bymeans of cap screws 40 and 41. These cap screws extend through slots 42and 43 respectively in said planar surface and are tightened intoaligned tapped holes provided in the locating bracket 32.

A cam member 44 is yieldably attached to the planar surface 39 by meansof a pair of spaced and upwardly directed bolt members 45 and 46 theheads of which are seated in appropriate apertures provided in the lowerplanar surface 39 (FIG. 4). Extending in an upwardly direction the shankportions of bolts 45 and 46 pass through and beyond slots 47 (one onlyshown in FIG. 4) with their upper ends having a biasing means assembledthereon for continually urging cam member 44 to that position shown inFIGS. 1, 3 and 4. This biasing means includes coil springs 48 and 49\(FIG. 1) which are assembled under tension on their respective bolts 45and 46 by means of washers 50 and 51 and nuts 52 and 53 respectively.

A further biasing means continually urges the cam member 44 in thedirection of the indicating arrow 54 in FIG. 2 and includes a pair ofspaced spring wires 55 and 56 with one end of each being anchored in acentrally disposed and upwardly directed lug 57 which forms an integralpart of the forward side of the planar surface 39. These spring wires 55and 56 are assembled in the lug 57 by means of set screws 58 (FIG. I)and extending from said lug the free ends of the spring wires are formedso as to bear against the forward side of the cam member 44.

Extending in the same general direction as spring wires 55 and 56 and inclose proximity with the latter lug 57 is provided with fingers 59 and60 having vertically disposed recesses 61 and 62 respectively. Theserecesses are disposed in alignment with the ends of the spring wires andserve to provide clearance for the latter when cam member 44 is movedforwardly as will be more fully described hereinafter.

Referring now to FIGS. 1 and 2, which shows the carrier moving in thedirection of the indicating arrows 63 and 64 respectively, the camengaging surface 27 of the off-set lip 22 is first caused to contact atapered leading end 65 of the cam member 44 as the carrier is beingwithdrawn from the shed. Further movement of the carrier in thisdirection (FIG. 2) brings the off-set lip into contact with a rearcamming surface 66 of the cam member and is effective in pivoting thegripper finger 20 and its leading end 24 a distance sutficient to causethe latter to release the weft 26. During this movement cam 44 isdisplaced slightly in a forward direction against the biasing force ofspring wires 55 and 56 so that the portions of said springs in contactwith said cam are pushed into the clearance recesses 61 and 62 providedon fingers 59 and 60.

To assure that the carrier and its tape 1 1 remain in their intendedpath of travel when the off-set lip 22 is in contact with the cam member44 an elongated guide strip 67 is provided which is disposed so as to beengaged by the rear wall portion of the carrier. This guide strip has across-sectional configuration that is L- shaped and is attached to agenerally T-shaped support bracket 68 by means of bolts 69 (one onlyshown in FIG. 3). Support bracket 68 overlies the pathway of the carrierand is adjustably assembled to a rearwardly directed shelf 70, by meansof a bolt 71, that forms the upper surface of log 57.

Referring now to FIGS. 6 and 7 the trailing end of the cam member 44 isbeveled on the lower portion thereof as shown at 72 and is disposed soas to be contacted by the plow type camming surface 28 when the carrieris caused to move toward the shed or in the direction of the indicatingarrows 73 and 74 in FIGS. 6 and 7 respectively. The plow type cammingsurface is effective as the carrier continues to move toward the shed inupwardly displacing the cam member 44 against the action of springs 48and 49 (FIG. 4) and thereby prevent actuation of the gripper finger 20.

To summarize the operation the weft extending carrier enters a warp shedand is caused to meet the inserting carrier at a point near the centerthereof where it receives and grips a length of weft adjacent to its cutend which was introduced by said inserting carrier. Both carriers thenreverse their direction of travel and the extending carrier draws theweft through the retnainder of the shed. As the extending carrier isleaving the shed, the off-set lip 22 of its gripper finger 20 makescontact with cam member 44, and pivots said finger 6 and its leading end24 a sufficient distance to release the weft and complete thatparticular pick.

When the carrier again moves toward the shed to repeat the cyclepivoting of the gripper finger 20 it is prevented by the plow typecamming surface 28 of the off-set lip 22 raising and traveling along theunderside of cam member 44.

Although the present invention has been described in connection with apreferred embodiment, it is to be understood that modifications andvariations may be resorted to without departing from the spirit andscope of the invention as those skilled in the art will readilyunderstand. Such modifications and variations are considered to bewithin the purview and scope of the invention and the appended claims.

I claim:

1. In a shuttleless loom of the type for inserting single picks of weftinto separate sheds of warp threads by opposed reciprocating carriermembers carried on the free ends of flexible tapes, an improvedapparatus for controlling the actuation of the gripper finger of theweft extending carrier comprising:

a. camming means mounted on said loom in a manner providing for movementbetween an operative position where it is contacted by the weft carrierto releast wefi from the gripper finger and in inoperative positionwhere no contact causing operation of the gripper finger is effected;

b. means defining an off set lip forming one end of the gripper fingerdisposed for operative engagement with said camming means having;

1. a forward vertical side defining a first cam engaging surface foractuating the gripper finger to release the weft as the carrier is beingwithdrawn from the shed;

2. an upper horizontal surface with a downwardly tapered leading enddefining a second cam engaging surface for displacing said camming meansto prevent actuation of the gripper finger during movement of thecarrier into the shed, said camming means including:

A. a biasing means for returning said camming means to its operatingposition after being displaced by said second cam engaging surface; and

B. a further biasing means for continually urging said camming meanstoward its position of engagement with said first cam engaging surface.

1. In a shuttleless loom of the type for inserting single picks of weftinto separate sheds of warp threads by opposed reciprocating carriermembers carried on the free ends of flexible tapes, an improvedapparatus for controlling the actuation of the gripper finger of theweft extending carrier comprising: a. camming means mounted on said loomin a manner providing for movement between an operative position whereit is contacted by the weft carrier to releast weft from the gripperfinger and in inoperative position where no contact causing operation ofthe gripper finger is effected; b. means defining an off set lip formingone end of the gripper finger disposed for operative engagement withsaid camming means having;
 1. a forward vertical side defining a firstcam engaging surface for actuating the gripper finger to release theweft as the carrier is being withdrawn from the shed;
 2. an upperhorizontal surface with a downwardly tapered leading end defining asecond cam engaging surface for displacing said camming means to preventactuation of the gripper finger during movement of the carrier into theshed, said camming means including: A. a biasing means for returningsaid camming means to its operating position after being displaced bysaid second cam engaging surface; and B. a further biasing means forcontinually urging said camming means toward its position of engagementwith said first cam engaging surface.
 2. an upper horizontal surfacewith a downwardly tapered leading end defining a second cam engagingsurface for displacing said camming means to prevent actuation of thegripper finger during movement of the carrier into the shed, saidcamming means including: A. a biasing means for returning said cammingmeans to its operating position after being displaced by said second camengaging surface; and B. a further biasing means for continually urgingsaid camming means toward its position of engagement with said first camengaging surface.